Problem: A new airplane SuperPuperJet has an infinite number of rows, numbered with positive integers starting with 1 from cockpit to tail. There are six seats in each row, denoted with letters from 'a' to 'f'. Seats 'a', 'b' and 'c' are located to the left of an aisle (if one looks in the direction of the cockpit), while seats 'd', 'e' and 'f' are located to the right. Seats 'a' and 'f' are located near the windows, while seats 'c' and 'd' are located near the aisle. 

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It's lunch time and two flight attendants have just started to serve food. They move from the first rows to the tail, always maintaining a distance of two rows from each other because of the food trolley. Thus, at the beginning the first attendant serves row 1 while the second attendant serves row 3. When both rows are done they move one row forward: the first attendant serves row 2 while the second attendant serves row 4. Then they move three rows forward and the first attendant serves row 5 while the second attendant serves row 7. Then they move one row forward again and so on.

Flight attendants work with the same speed: it takes exactly 1 second to serve one passenger and 1 second to move one row forward. Each attendant first serves the passengers on the seats to the right of the aisle and then serves passengers on the seats to the left of the aisle (if one looks in the direction of the cockpit). Moreover, they always serve passengers in order from the window to the aisle. Thus, the first passenger to receive food in each row is located in seat 'f', and the last one — in seat 'c'. Assume that all seats are occupied.

Vasya has seat s in row n and wants to know how many seconds will pass before he gets his lunch.

Input

The only line of input contains a description of Vasya's seat in the format ns, where n (1 ≤ n ≤ 1018) is the index of the row and s is the seat in this row, denoted as letter from 'a' to 'f'. The index of the row and the seat are not separated by a space.

Output

Print one integer — the number of seconds Vasya has to wait until he gets his lunch.

Examples

Input

1f


Output

1


Input

2d


Output

10


Input

4a


Output

11


Input

5e


Output

18

Note

In the first sample, the first flight attendant serves Vasya first, so Vasya gets his lunch after 1 second.

In the second sample, the flight attendants will spend 6 seconds to serve everyone in the rows 1 and 3, then they will move one row forward in 1 second. As they first serve seats located to the right of the aisle in order from window to aisle, Vasya has to wait 3 more seconds. The total is 6 + 1 + 3 = 10.

Solution (in JAVA):

Solution:
import java.io.File;import java.io.FileInputStream;import java.io.FileNotFoundException;
import java.io.IOException;import java.io.InputStream;import java.io.PrintWriter;
import java.security.AccessControlException;import java.util.List;public class _p000725B {
static public void main(final String[] args) throws IOException{p000725B._main(args);}

static class p000725B extends Solver{public p000725B(){singleTest=true;}@Override public 
void solve()throws IOException{String ns=sc.nextLine();long n=Long.parseLong(ns.substring(0,
ns.length()-1));String s=ns.substring(ns.length()-1);long res=((n-1)%4==0?4l*(n-
1):((n-2)%4==0?7+4l*(n-2):((n-3)%4==0?4l*(n-3):7+4l*(n-4))));switch(s){case"f":res++;
break;case"e":res+=2;break;case"d":res+=3;break;case"a":res+=4;break;case"b":res
+=5;break;case"c":res+=6;break;}pw.println(res);}static public void _main(String[]
args)throws IOException{new p000725B().run();}}static class MyScanner{private StringBuilder 
cache=new StringBuilder();int cache_pos=0;private int first_linebreak=-1;private 
int second_linebreak=-1;private StringBuilder sb=new StringBuilder();private InputStream 
is=null;public MyScanner(final InputStream is){this.is=is;}public String charToString(final 
int c){return String.format("'%s'",c=='\n'?"\\n":(c=='\r'?"\\r":String.valueOf((char)c)));
}public int get(){int res=-1;if(cache_pos<cache.length()){res=cache.charAt(cache_pos);
cache_pos++;if(cache_pos==cache.length()){cache.delete(0,cache_pos);cache_pos=0;
}}else{try{res=is.read();}catch(IOException ex){throw new RuntimeException(ex);}
}return res;}private void unget(final int c){if(cache_pos==0){cache.insert(0,(char)c);
}else{cache_pos--;}}public String nextLine(){sb.delete(0,sb.length());int c;boolean 
done=false;boolean end=false;while((c=get())!=-1){if(check_linebreak(c)){done=true;
if(c==first_linebreak){if(!end){end=true;}else{cache.append((char)c);break;}}else 
if(second_linebreak!=-1 && c==second_linebreak){break;}}if(end && c!=first_linebreak 
&& c!=second_linebreak){cache.append((char)c);break;}if(!done){sb.append((char)c);
}}return sb.toString();}private boolean check_linebreak(int c){if(c=='\n'|| c=='\r')
{if(first_linebreak==-1){first_linebreak=c;}else if(c!=first_linebreak && second_linebreak
==-1){second_linebreak=c;}return true;}return false;}public int nextInt(){return 
Integer.parseInt(next());}public long nextLong(){return Long.parseLong(next());}
public boolean hasNext(){boolean res=false;int c;while((c=get())!=-1){if(!check_linebreak(c)
&& c!=' '&& c!='\t'){res=true;unget(c);break;}}return res;}public String next(){
sb.delete(0,sb.length());boolean started=false;int c;while((c=get())!=-1){if(check_linebreak(c)
|| c==' '|| c=='\t'){if(started){unget(c);break;}}else{started=true;sb.append((char)c);
}}return sb.toString();}public int nextChar(){return get();}public boolean eof()
{int c=get();boolean res=false;if(c!=-1){unget(c);}else{res=true;}return res;}public 
double nextDouble(){return Double.parseDouble(next());}}static abstract class Solver
{protected String nameIn=null;protected String nameOut=null;protected boolean singleTest
=false;protected MyScanner sc=null;protected PrintWriter pw=null;private int current_test
=0;private int count_tests=0;protected int currentTest(){return current_test;}protected 
int countTests(){return count_tests;}private void process()throws IOException{if(!singleTest)
{count_tests=sc.nextInt();sc.nextLine();for(current_test=1;current_test<=count_tests;
current_test++){solve();pw.flush();}}else{count_tests=1;current_test=1;solve();}
}abstract protected void solve()throws IOException;public void run()throws IOException
{boolean done=false;try{if(nameIn!=null){if(new File(nameIn).exists()){try(FileInputStream 
fis=new FileInputStream(nameIn);PrintWriter pw0=select_output();){select_output();
done=true;sc=new MyScanner(fis);pw=pw0;process();}}else{throw new RuntimeException("File "
+new File(nameIn).getAbsolutePath()+" does not exist!");}}}catch(IOException | AccessControlException 
ex){}if(!done){try(PrintWriter pw0=select_output();){sc=new MyScanner(System.in);
pw=pw0;process();}}}private PrintWriter select_output()throws FileNotFoundException
{if(nameOut!=null){return new PrintWriter(nameOut);}return new PrintWriter(System.out);
}}static abstract class Tester{static public int getRandomInt(final int min,final 
int max){return(min+(int)Math.floor(Math.random()*(max-min+1)));}static public long 
getRandomLong(final long min,final long max){return(min+(long)Math.floor(Math.random()
*(max-min+1)));}static public double getRandomDouble(final double min,final double 
maxExclusive){return(min+Math.random()*(maxExclusive-min));}abstract protected void 
testOutput(final List<String>output_data);abstract protected void generateInput();
abstract protected String inputDataToString();private boolean break_tester=false;
protected void beforeTesting(){}protected void breakTester(){break_tester=true;}
public boolean broken(){return break_tester;}}}